Are We Still Capable Of Getting A <1c Cet Month?

[Anti-Mild]

I don't know if this is in the right forum but I'm sure the mods will shift it if it isn't !

For most cold rampers the holy grail of winters is 1962/63 which was fortunate enough to experience 2 sub zero months. Then there was 1946/47 with a frigid February and then there was 1978/79 with a very cold January and almost equally cold February. Looking back over the last 100 years there has only been 16 months with a CET below 1c which amounts to one every 18.75 winter months or 1 winter in 6 providing a very cold month.

That said, the last <1c month was waaaay back in January 1987; 59 winter months ago, indeed the last time we had a winter month below 3c was January 1997.

Obviously in this era of global warming (or climate change, depending on your own beliefs ) a very cold month becomes very unlikely but does it become impossible?

In all of the months in the last 100 years that were very cold, the common factor is a prolonged or repeated Easterly regime bringing sub-zero temperatures and snowfall, something that we have been achingly close to both last winter and in February 2005 - it seems we have been unlucky :blush: !

It would seem that all we need is a strong blocking HP in just the right place to allow the right conditions to spill over us from the east. Since it seems that we may be in a particularly blocked spell of weather surely one of these times we will get lucky! So, is it possible for us here in Britain to experience a month the likes of which many of our members will only have read about?

[Shiny_Bottom_1]

Personally, I would say yes. But when is a different question.

The 40's had a cracking time, with 5 years having a month below 1oC.

Three years 80's, One in the 70's, one in the 60's, one in the 50's, one in the 20's and one in the teens...all had a month below 1oC.

Statistically, it has been the longest period without a month <1oC over the last 100 years.

This year...who knows, but I dont think its impossible.

[Paranoid]

I'd say yes. We need a decent easterly wind off the continent, which is something we got this summer, giving us similar weather to the continent. If we have similar conditions in winter i'd say we're in for a prolonged cold spell, like the hot spell we had in July this year.

[kold weather]

I'd also say yes, its possible. Last winter we proved that we can still get several fairly widespread ice days and we also proved we can get those ultra-low temps as well with one max in newcastle at -7C during the Dec easterly, so the extremes of cold are no doubt possible.

The only thing now is that now its harder to achieve given how much warmer the seas around the Artic are but its possible if all the parts still come into play.

[Pennine Ten Foot Drifts]

I think perhaps the question should be, is it still as likely now as in the past that we will experience a <1c month, and just going on weather statistics the answer has to be 'no'. Whilst it is always of course going to be possible to have a <1c month because the synoptic ingredients are still theoretically 'available' for the UK, it really seems as if the chances for those synoptic ingredients coming together seem to be worse. Whilst I fully understand that probability is seperate from past experience, (i.e. tossing 'heads' six times in a row does not make 'tails' more likely the next time), weather seems a little different in so far as previous observation certainly seems to point to trends and as such we seem to be trending further and further away from experiencing the types of setups which produce <1c months.

[Essan]

I guarantee will get one. Whether any of us are still alive to experience it is a different matter .... :blush:

The main thing we need is to have lower nighttime temps - and regardless of your views on climate change, this is where the difficulty arises as UHI/Suburban Heat Effect becomes ever more pronounced and widespread. But it's not impossible.

[Guest Daniel]

I don't know if this is in the right forum but I'm sure the mods will shift it if it isn't !

For most cold rampers the holy grail of winters is 1962/63 which was fortunate enough to experience 2 sub zero months. Then there was 1946/47 with a frigid February and then there was 1978/79 with a very cold January and almost equally cold February. Looking back over the last 100 years there has only been 16 months with a CET below 1c which amounts to one every 18.75 winter months or 1 winter in 6 providing a very cold month.

That said, the last <1c month was waaaay back in January 1987; 59 winter months ago, indeed the last time we had a winter month below 3c was January 1997.

Obviously in this era of global warming (or climate change, depending on your own beliefs ) a very cold month becomes very unlikely but does it become impossible?

In all of the months in the last 100 years that were very cold, the common factor is a prolonged or repeated Easterly regime bringing sub-zero temperatures and snowfall, something that we have been achingly close to both last winter and in February 2005 - it seems we have been unlucky :blush: !

It would seem that all we need is a strong blocking HP in just the right place to allow the right conditions to spill over us from the east. Since it seems that we may be in a particularly blocked spell of weather surely one of these times we will get lucky! So, is it possible for us here in Britain to experience a month the likes of which many of our members will only have read about?

Of course we can get freezing cold again. As I keep on pointing out time and time again. we are just going through a warm phase which will come to an end. The sun is set to go in a quite mode before mid century and more and more ice is pouring from Greenland into the sea which if it slows down the gulf that would change weather patterns favoring freezing cold. Now the favored weather pattern for great winter cold is a cool August followed by a cool Autumn. Now in recent years our summers have been warm which as lead to warmer Autumns and then warm winters. But this pattern could well be comming to an end. After a warm June and hot July this August has been much cooler and possibly it would turn out to be one of the coldest of recent times. if this follows through into Autumn and we get a cool Atutumn there a real chance of a major freeze this comming winter. Now that weather pattern has occured many time in the past but not in recent times. But this year could be very differnt.

[Coopsy]

As I keep on pointing out time and time again. we are just going through a warm phase which will come to an end.

I thought you might slip that one in

[BLAST FROM THE PAST]

It's really got to be down to three issues.

1] Source: The air has to be intensely cold to withstand moderation around our shores. 2] Timing: Mid Feb onwards and we are looking too late as of last two winters, it needs to arrive by 1st week of Feb at extreme latest...by this time the source won't be cold enough to produce sustained low temps to record CET <1C.

3] Positioning and stabilty of block: It has to be in the right place to feed the cold temps in and has to be stable so that the pattern remains to continue the feed.

These factors figured in both the last two winters and near misses were experienced widely.

This July was good opposite season example. Although all time UK temp wasn't really sniffed at the overall temp did the business. Stability, timing and source were in place.

It has been proved and evident that the source still exists eg European winter last year but timing and stabilty/positioning has been out.

BFTP

[Pennine Ten Foot Drifts]

This July was good opposite season example. Although all time UK temp wasn't really sniffed at the overall temp did the business. Stability, timing and source were in place.

Exactly. I wonder how many maximum temperature monthly records have been broken since 1987 compared to record monthly minimum records having been broken. I would guess that maximum monthly temperature records have been broken then broken again then broken again over the past eighteen years, I wonder if any monthly minimum records have been broken over the same period ??????

[Stratos Ferric]

As PTFD suggests, in theory yes, in practice - possibly not at present. I agree with Essan's comment, the point being that it's not timebound, but I disagree with the "all we need is cold nights" theory. Warmer nights do disproportionatley account for the change in average winter temperature over the last thirty years, but they do not account for it all.

The attached plot explains my position.

You could quite easily draw two trend lines through the data. The first, and most pertinent, would be through the various minima. This has a very scary good fit, suggesting that the minimum for a winter month in the even larger teapot is only around 3.5C. The gradient of this line is about 1C/7 years, or about 1C per 12 if you take 62/3 as a complete freak. Scary!

The second is the general trend line: applying a regression would give a gradient of about 2C across the period, so that's just shy of 1C / 20 years. A similar line for the max temperatures would yield around 1C across the whole, though it is possible to argue for a more or less flat line starting with the outlier in 1961. What is clear is the increasing cluster of months closer to this line. Finally, parallel to, but below, the main regression line I've drawn the line for the 95% confidence; this is the line outside which there should be a 20% chance (approximately) of an individual month falling. This series has 180 months in it, and 6 do indeed fall below this line, though none since 1987, that's getting on for 80 winter months, now well nudging the point of statistical significance (i.e. the absence of a cold month as defined is not "by chance", but likely indicative of underlying trend, i.e. warming).

All of this stacks up nicely with theory. It is easier to get a reduction in winter cold than it is to dramatically increasing upside warmth. The former requires a set of circumstances that introduce cold air; making these less prevalent, and / or a change in the actual ambient characteristic of the air mass would shove minima upwards. At the top end the limits are more bounded by incoming energy. There is a theoretical limit to the maximum temperature in a winter month and normal volatility is such that we are usually far closer to this threshold than we are to the upper limits for high minimum temperatures. It could be argued, therefore, that increases in the trend of the maximum are actually a good indicator of background warming and the regression line of about 1.5C across this period is roughly consistent with most current claims.

In summary, therfore: it's very unlikely that we will see another 1C winter month for quite some time, and certainly until we see the whole system start to cool again. A 1C month now is about as likely as a -1C month was thirty or so years ago, and perhaps less likely even than that given the long period since a month fell below the 95% tail. On the basis of my analysis, the statistical minimum is now around 2C, a degree of coldness c.f. the current norm which has been matched four times in this data series. The however, is that we seem to have far less volatility now, making this sort of cold outlier less likely than reference simply to the background warming would suggest.

Of course we can get freezing cold again. As I keep on pointing out time and time again. we are just going through a warm phase which will come to an end. The sun is set to go in a quite mode before mid century and more and more ice is pouring from Greenland into the sea which if it slows down the gulf that would change weather patterns favoring freezing cold. Now the favored weather pattern for great winter cold is a cool August followed by a cool Autumn. Now in recent years our summers have been warm which as lead to warmer Autumns and then warm winters. But this pattern could well be comming to an end. After a warm June and hot July this August has been much cooler and possibly it would turn out to be one of the coldest of recent times. if this follows through into Autumn and we get a cool Atutumn there a real chance of a major freeze this comming winter. Now that weather pattern has occured many time in the past but not in recent times. But this year could be very differnt.

Daniel,

Are you predisposed to arguing for cold because you get excited by the snow, or do you actually believe this "science"? I certainly don't see how a month that is likley to turn out around average (CET) can justifiably be called "one of the coldest of recent times". I can't remember a time when you weren't spending summer / autumn predicting the mummy, daddy, grandfather and in-laws of all winters to come.

[snowsure]

The second is the general trend line: applying a regression would give a gradient of about 2C across the period, so that's just shy of 1C / 20 years.

The general trend line looks more like 1C/30 years to me. Would you agree? Quite "shy" of 1C / 20 years.

Good post though!

[The Penguin]

Of course we can get freezing cold again. As I keep on pointing out time and time again. we are just going through a warm phase which will come to an end. The sun is set to go in a quite mode before mid century and more and more ice is pouring from Greenland into the sea which if it slows down the gulf that would change weather patterns favoring freezing cold. Now the favored weather pattern for great winter cold is a cool August followed by a cool Autumn. Now in recent years our summers have been warm which as lead to warmer Autumns and then warm winters. But this pattern could well be comming to an end. After a warm June and hot July this August has been much cooler and possibly it would turn out to be one of the coldest of recent times. if this follows through into Autumn and we get a cool Atutumn there a real chance of a major freeze this comming winter. Now that weather pattern has occured many time in the past but not in recent times. But this year could be very differnt.

Daniel, I have an advantage over you in that I am getting uncomfortably close to seeing my fiftieth August, autumn and winter, and I therefore have slightly more experience of weather than I suspect you do, but I have to tell you that your premise is simply wrong.

I acknowledge that the weather I experience may be different from you or the CET area, for instance, but from memory the summers of 1976, 1985, and 1995 were either pleasantly or outstandingly warm while the following winters were notably cold. Other years have had coolish wet summers followed by warmer than usual conditions throughout the winter.

In any case, your argument regarding cold winters following cool summers by necessity, seems over generalised. You might equally say that cool summers would automatically follow cold winters. And then you would get into a never-ending monorail pattern of weather that could not break out of it’s own laws of progression. This plainly is not the case. You admit yourself that June and July were warm and August is cooler. If the pattern of weather can change over the space of a month, it can obviously change over the space of a season or two.

We are still some way away from accurate weather, never mind climate, prediction. Certainly too far away to be able to link August synoptics to those in December, January and February. Even the SACRA fundamentalists would have to admit that all their best planning for a freezing winter can be completely shot to pieces if some butterfly in the Amazon takes off and goes the in the wrong direction.

Having said all that, you have as much right to your opinion as anyone else. Please just don’t get too carried away with unproven or simplistic methods of analysis.

Edit – apologies; I see that other similar comments have been added while I was composing: this now looks like ganging up and it was certainly not meant as such.

[Stratos Ferric]

The general trend line looks more like 1C/30 years to me. Would you agree? Quite "shy" of 1C / 20 years.

Good post though!

Yes, apologies, and careless of me. I typed a rough guess before calculating it; correctly it's about 1.5C over the 47 years, which indeed makes it around 1C per 30. My core argument doesn't rely on the central trend though, and in any case, a point I didn't make in the main piece, is that I've had to fudge slightly to get the regression stats, using the winter average. What we should really look at is the trend for individual months, though be assured the story would be pretty much the same.

Daniel,

...

Please just don’t get too carried away with unproven or simplistic methods of analysis.

Oh I don't know, why break the habit of a N-W lifetime?

[BLAST FROM THE PAST]

Exactly. I wonder how many maximum temperature monthly records have been broken since 1987 compared to record monthly minimum records having been broken. I would guess that maximum monthly temperature records have been broken then broken again then broken again over the past eighteen years, I wonder if any monthly minimum records have been broken over the same period ??????

PTFD

Here is the surprising or maybe not result

Warmest Jan: 1921 at 7.3C

Feb: 1945 previous at 7.1 exceeded twice in 1990/98 at 7.3C

Mar: 1938/57 AT 9.2C

Apr: 1943 at 10.5C

May: 1919 previous at 13.5C exceeded in 1992 at 13.6C

June: 1976 at 17C

July: 1983 previous at 19.5C exceeded in 06 at ....

Aug: 1975 previous at 18.7C exceeded in 1995 at 19.2C and 1997 at 18.9C

Sept: 1929 previous at 15.3C exceeded 1999 at 15.6C

Oct: 1960 previous at 13C exceeded 2005 at 13.1C

Nov: 1939 previous at 8.7C exceeded 1994 at 10.1C

Dec: 1934/74 at 8.1C

So since 1987 as the bench mark record warm months were achieved on 9 occasions. Coldest month never been set since 1987.

BFTP

[BLAST FROM THE PAST]

I can't remember a time when you weren't spending summer / autumn predicting the mummy, daddy, grandfather and in-laws of all winters to come.

[BristolBaggie]

Good riddance to this rubbish summer a few weeks of warm weather in July and thats been our lot.

Bring on global warming

and a Severe Winter 06/07

:lol:

[Thundery wintry showers]

SF's statistics seem, to me, to back up the view that synoptics are changing along with the mean global temperature.

For example, Moscow can still have exceptionally cold months (December 2002 was a full 6.7C below the 1961-90 average) but in Britain, we have struggled to get even below a CET of 3C since the late 1980s. The frequency of cold airmasses over Britain has declined, and when they do occur, they are moderated by warmer seas, and over the past few years the Arctic has been exceptionally warm.

I still remember the northerly of 13 February 2005 as a prime example, when the temperature never fell below the long-term average despite a northerly straight from the pole. February 2005 would probably have been a very cold month if the cold air sources hadn't been some 10C above the long-term average.

I think it is possible- March 2006 was about 3C below the 1961-90 average, and 3.5C below 1971-2000, for the 1st-23rd, but then the anomaly was largely negated by the exceptionally warm last week. But, as others have said, highly unlikely.

[J10]

During the period of the not getting below 1c in a calendar month drought, has there been a continuous period of 30-31 days where the CET on average been below 1c, I wonder if Mr Data would be able to help.

The recent milder trend makes a sub 1c month less likely but IMO not impossible.

[snowsure]

I still remember the northerly of 13 February 2005 as a prime example, when the temperature never fell below the long-term average despite a northerly straight from the pole. February 2005 would probably have been a very cold month if the cold air sources hadn't been some 10C above the long-term average.

Does anyone know if we are receiving more than our "normal" share of N winds?

My observations appears to show a plethora of NW-N-NE winds whatever the season. (I am only speaking for one part of Doncaster so you may not agree. That is why I am wanting to know about the "bigger picture." )

[BLAST FROM THE PAST]

SF's statistics seem, to me, to back up the view that synoptics are changing along with the mean global temperature.

For example, Moscow can still have exceptionally cold months (December 2002 was a full 6.7C below the 1961-90 average) but in Britain, we have struggled to get even below a CET of 3C since the late 1980s. The frequency of cold airmasses over Britain has declined, and when they do occur, they are moderated by warmer seas, and over the past few years the Arctic has been exceptionally warm.

TWS

Indeed the last time the arctic was as warm/ in fact it was warmer was in the 30s extreme cold months were not around for the UK then either.

BFTP

[Thundery wintry showers]

I seem to recall that the frequency of northerlies in 2005 was above normal, but often in the form of moderated northerlies, with air originating in the western Atlantic and coming "up and around" a mid-Atlantic high. February 2005 was one of the most "northerly" February months on record.

I think in the past few years the frequency of cold synoptic setups has returned to more usual levels, but with the cold air sources generally being exceptionally warm. Last winter was an exception on the easterly front, with Asia and Russia being cold, but we never picked up easterly winds at the right time to bring a severely cold spell.

[kippure]

Does anyone know if we are receiving more than our "normal" share of N winds?

My observations appears to show a plethora of NW-N-NE winds whatever the season. (I am only speaking for one part of Doncaster so you may not agree. That is why I am wanting to know about the "bigger picture." )

They seem to me to be more common , and this comes from looking at nature. Odd you may ask , however take for example trees! Through the 80,s our weather was mainly West south west nearly all the time. The strength of this flow has decreased quite alot, and so ive noticed trees are,nt growing over to one side anymore. We seem to be experiencing a change to quite alot of North to North East flows, no matter what time of the year it is.

[snowsure]

I seem to recall that the frequency of northerlies in 2005 was above normal, but often in the form of moderated northerlies, with air originating in the western Atlantic and coming "up and around" a mid-Atlantic high. February 2005 was one of the most "northerly" February months on record.

I think in the past few years the frequency of cold synoptic setups has returned to more usual levels, but with the cold air sources generally being exceptionally warm. Last winter was an exception on the easterly front, with Asia and Russia being cold, but we never picked up easterly winds at the right time to bring a severely cold spell.

Thanks TWS. If the western Atlantic was to decrease in temperature, I assume that the moderating effects would be, well, moderated. I do not know if this is plausible or likely. Neither do I know if un-moderated Polar winds will make a return.

Once again, thanks for your response. :lol:

[Anti-Mild]

Perhaps this year, given that the Pole is starting off colder than it has been in recent years. As I mentioned earlier there is a huge element of luck involved and maybe this will be 3rd time lucky!!

For what it's worth, while I think it is possible I don't think it'll happen this year. My preliminary forecast gives CET's of December - 4.4c, January - 3.4c and February - 4.2c.